#include<stdio.h>
#include<stdlib.h>
int main()
{
	int i,j;
	int x=0;
	int y=5;
	
	int velocity_x=1;
	int velocity_y=1;
	int left=0;
	int right=20;
	int top=0;
	int bottom=10;
	
	while(1)
	{
		x=x+velocity_x;
		y=y+velocity_y;
		
		system("cls");
		
		
	for(i=0;i<x;i++)
		printf("\n");
	for(j=0;j<y;j++)
		printf(" ");
	printf("o");
	printf("\n");
	
	if((x==top)||(x==bottom))
		velocity_x=-velocity_x;
	if((y==left)||(y==right))
		velocity_y=-velocity_y;
	}
	return 0;
}